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  <div class="section" id="numpy-ma-maskedarray-sort">
<h1>numpy.ma.MaskedArray.sort<a class="headerlink" href="#numpy-ma-maskedarray-sort" title="Permalink to this headline">¶</a></h1>
<p>method</p>
<dl class="method">
<dt id="numpy.ma.MaskedArray.sort">
<code class="sig-prename descclassname">MaskedArray.</code><code class="sig-name descname">sort</code><span class="sig-paren">(</span><em class="sig-param">self</em>, <em class="sig-param">axis=-1</em>, <em class="sig-param">kind=None</em>, <em class="sig-param">order=None</em>, <em class="sig-param">endwith=True</em>, <em class="sig-param">fill_value=None</em><span class="sig-paren">)</span><a class="reference external" href="https://github.com/numpy/numpy/blob/v1.18.1/numpy/ma/core.py#L5549-L5630"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#numpy.ma.MaskedArray.sort" title="Permalink to this definition">¶</a></dt>
<dd><p>Sort the array, in-place</p>
<dl class="field-list simple">
<dt class="field-odd">Parameters</dt>
<dd class="field-odd"><dl class="simple">
<dt><strong>a</strong><span class="classifier">array_like</span></dt><dd><p>Array to be sorted.</p>
</dd>
<dt><strong>axis</strong><span class="classifier">int, optional</span></dt><dd><p>Axis along which to sort. If None, the array is flattened before
sorting. The default is -1, which sorts along the last axis.</p>
</dd>
<dt><strong>kind</strong><span class="classifier">{‘quicksort’, ‘mergesort’, ‘heapsort’, ‘stable’}, optional</span></dt><dd><p>The sorting algorithm used.</p>
</dd>
<dt><strong>order</strong><span class="classifier">list, optional</span></dt><dd><p>When <em class="xref py py-obj">a</em> is a structured array, this argument specifies which fields
to compare first, second, and so on.  This list does not need to
include all of the fields.</p>
</dd>
<dt><strong>endwith</strong><span class="classifier">{True, False}, optional</span></dt><dd><p>Whether missing values (if any) should be treated as the largest values
(True) or the smallest values (False)
When the array contains unmasked values sorting at the same extremes of the
datatype, the ordering of these values and the masked values is
undefined.</p>
</dd>
<dt><strong>fill_value</strong><span class="classifier">{var}, optional</span></dt><dd><p>Value used internally for the masked values.
If <code class="docutils literal notranslate"><span class="pre">fill_value</span></code> is not None, it supersedes <code class="docutils literal notranslate"><span class="pre">endwith</span></code>.</p>
</dd>
</dl>
</dd>
<dt class="field-even">Returns</dt>
<dd class="field-even"><dl class="simple">
<dt><strong>sorted_array</strong><span class="classifier">ndarray</span></dt><dd><p>Array of the same type and shape as <em class="xref py py-obj">a</em>.</p>
</dd>
</dl>
</dd>
</dl>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<dl class="simple">
<dt><a class="reference internal" href="numpy.ndarray.sort.html#numpy.ndarray.sort" title="numpy.ndarray.sort"><code class="xref py py-obj docutils literal notranslate"><span class="pre">numpy.ndarray.sort</span></code></a></dt><dd><p>Method to sort an array in-place.</p>
</dd>
<dt><a class="reference internal" href="numpy.ma.argsort.html#numpy.ma.argsort" title="numpy.ma.argsort"><code class="xref py py-obj docutils literal notranslate"><span class="pre">argsort</span></code></a></dt><dd><p>Indirect sort.</p>
</dd>
<dt><code class="xref py py-obj docutils literal notranslate"><span class="pre">lexsort</span></code></dt><dd><p>Indirect stable sort on multiple keys.</p>
</dd>
<dt><a class="reference internal" href="numpy.ma.MaskedArray.searchsorted.html#numpy.ma.MaskedArray.searchsorted" title="numpy.ma.MaskedArray.searchsorted"><code class="xref py py-obj docutils literal notranslate"><span class="pre">searchsorted</span></code></a></dt><dd><p>Find elements in a sorted array.</p>
</dd>
</dl>
</div>
<p class="rubric">Notes</p>
<p>See <code class="docutils literal notranslate"><span class="pre">sort</span></code> for notes on the different sorting algorithms.</p>
<p class="rubric">Examples</p>
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">a</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">ma</span><span class="o">.</span><span class="n">array</span><span class="p">([</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">5</span><span class="p">,</span> <span class="mi">4</span><span class="p">,</span> <span class="mi">3</span><span class="p">],</span><span class="n">mask</span><span class="o">=</span><span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">0</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="c1"># Default</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">a</span><span class="o">.</span><span class="n">sort</span><span class="p">()</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">a</span>
<span class="go">masked_array(data=[1, 3, 5, --, --],</span>
<span class="go">             mask=[False, False, False,  True,  True],</span>
<span class="go">       fill_value=999999)</span>
</pre></div>
</div>
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">a</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">ma</span><span class="o">.</span><span class="n">array</span><span class="p">([</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">5</span><span class="p">,</span> <span class="mi">4</span><span class="p">,</span> <span class="mi">3</span><span class="p">],</span><span class="n">mask</span><span class="o">=</span><span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">0</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="c1"># Put missing values in the front</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">a</span><span class="o">.</span><span class="n">sort</span><span class="p">(</span><span class="n">endwith</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">a</span>
<span class="go">masked_array(data=[--, --, 1, 3, 5],</span>
<span class="go">             mask=[ True,  True, False, False, False],</span>
<span class="go">       fill_value=999999)</span>
</pre></div>
</div>
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">a</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">ma</span><span class="o">.</span><span class="n">array</span><span class="p">([</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">5</span><span class="p">,</span> <span class="mi">4</span><span class="p">,</span> <span class="mi">3</span><span class="p">],</span><span class="n">mask</span><span class="o">=</span><span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">0</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="c1"># fill_value takes over endwith</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">a</span><span class="o">.</span><span class="n">sort</span><span class="p">(</span><span class="n">endwith</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">fill_value</span><span class="o">=</span><span class="mi">3</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">a</span>
<span class="go">masked_array(data=[1, --, --, 3, 5],</span>
<span class="go">             mask=[False,  True,  True, False, False],</span>
<span class="go">       fill_value=999999)</span>
</pre></div>
</div>
</dd></dl>

</div>


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